This invention relates to an apparatus for increasing the mobility of wheelchair-bound persons, more specifically, it relates to a device suitable for elevating and forwardly tipping the seat of wheelchairs of a variety of conventional designs to assist a disabled person to arise more readily from or be seated in a wheelchair.
Disabled or aged persons confined to the use of a wheelchair for mobility often experience difficulty or require assistance when arising from the seat of a wheelchair. A relatively small forward tilt and rise of the seat assists the disabled person very substantially in standing and balancing on his feet.
An attendant is often required to lift the disabled person upward to assist him or her in attaining a standing position. Lifting of the incapacitated person is stressful for the attendant and may also expose the patient to harmful physical stress.
An additional hazard is created when the incapacitated person arising from a seated position in a wheelchair pushes against the wheelchair in order to propel his body upward and forward. If the brake(s) of the chair have not been fully engaged, the horizontal force exerted against the wheelchair may cause the chair to roll out from under the patient before the patient is fully standing on his feet, and thus cause a dangerous fall.
There are currently available wheel chairs and stationery chairs designed for disabled persons which embody means for elevating and forwardly tipping the chair seat to assist the seated occupant to arise to his/her feet. The elevating and forward seat-tipping in these earlier devices utilized many different mechanical and motor driven mechanisms to activate raised and angled repositioning of a seat when occupied by a disabled person. One such mechanism embodied in a stationery chair is disclosed in U.S. Pat. No. 4,007,960 (Gaffney). Other motor driven mechanisms disclosing variations on the Gaffney device have been mounted in wheelchairs.
All the aforesaid motor driven seat elevating and repositioning mechanisms require that the mechanism be mounted within and integral with a stationary chair or wheel chair. These mechanisms are sizeable, heavy and expensive. Thus in a nursing home or hospital requiring a plurality of wheelchairs for disabled persons, including child-sized wheelchairs, the additional cost of providing wheelchairs having self contained elevating and seat tipping motorized mechanisms is considerable.
Moreover, wheelchairs equipped with heavy and physically bulky elevating and seat tipping mechanisms are awkward and often too heavy to negotiate stairs, ramps, and curbs, or to permit lifting the wheelchair into vans or buses. While the elevating and seat tipping wheelchair provides useful assistance to a disabled person, the weight of the elevating mechanism may, because of the considerable added weight, restrict the mobility of such a person confined to a wheelchair so equipped.
Heretofore, there have been no means available, other than those embodied within the chair itself, for elevating and forwardly tipping the seat of a conventional design invalid's wheelchair. The limitation on providing a device for elevating and forwardly tipping the seat of a variety of conventional wheelchairs resided in the sheer variability in the design of wheelchairs and the difficulty of securely gripping the frame of any of a variety of invalid wheelchairs to facilitate safely elevating and tipping, respectively, the seats thereof.